Safety device



Patented Jan. 2l, 1936 UNITED STATES PATENT OFFICE 9 Claims.

`valve which has a valve head carried by a stem which is keyed to a rotatable operating shaft. The operating shaft is provided with a spring which exerts pressure on the stem to hold it in contact with a fusible plug also carried in or by the operating shaft. *The spring is maintained under constant compression and is effectiveto actuate the stem in the event of fusing of the plug, and such actuation of the'stem is effective to seat or unseat the valve head according to the use for which the valve" is designed. The spring is so designed that it remains under compression even after it has actuated the valve stem,` thus it continues to exertvpressure on the valve stem tending to push the same outwardly even after the Vvalve stem has reached its limit OfptWardAmOVement,

Other objects, novel features and advantages of this invention will become apparent from the following specification and accompanying drawing, wherein:

Fig. 1 is a side elevation of a Valve embodying the invention;

Fig. 2 is an end view thereof;

Fig. 3 is a section on the line 3--3 of Fig. 2 with the fusible plug in normal position, and

Fig. 4 is a similar fragmentary view with the valve stem actuated by the spring, the fusible plug having been melted.

The valve shown in the drawing is designed for normal manual operation and for automatic closing upon increase of temperature above a predetermined value. It is to be understood, however, that the invention is equally applicable toY a'valve designed for automatic opening upon temperature increase above a predetermined value andthat the difference between the two types of valve involves merely reversal of the arrangement of valve head and seat.

A casing I `is provided with an inlet aperture in which is arranged a valve seat I I. An operating shaft I2 is provided at its inner end with threads I3 which cooperate with threads I 4 formed on the inner surfacev of the casing I Il to effect axial movement of the shaft upon rotation thereof. A hand wheel I5 is keyed to the shaft I2. The shaft I2 is tubular and a stem I6 isslidably mounted therein. The left end of the stem IB is provided with an enlargement I 'I which fits into a recess in the valve head VI8 and a ring I9 fastened to the valve head I8 engages the enlargement I'I to hold the stem I6 and head I8 together. The valve head I 8 is preferably thus 5 mounted upon stem I6 so that it is free to rotate independentlyof the stem. The right end of the stem I 6 is threaded and carries nut 20 against which bears one end of a helical spring V2| ar ranged around the stem in a recess provided for 10 the purpose, the other end of the spring being in contact with the end wall of the recess.

The hand wheel I5 is secured to the shaft I2 1 by a lock nut 22. A plug 23 is threaded 'into said shaft. The plug 23 comprises a casing hav- 15 ing a tapered aperture which is filled with fusible material 24. A tapered sleeve 25 surrounds the part of the stem extending beyond the nut and engages both the nut 20 and the fusible material 24. The nut 20 normally seats in a recess 20 of corresponding configuration and serves to key the stem I6 to the shaft I2 for unitary rotation.

A gland 26 surrounds the shaft I2 and is held to the casing IIJ by bolts 2'I. Packings 28 are compressed by the gland and form a fluid-tight joint between the shaft and the casing.

In normal operation of the valve, the shaft I2 is rotated by manual operation of the hand wheel I5 to either seat the valve head I8 on the valve seat II or to unseat the same. the valve is open, the temperature increases beyond a predetermined value, the fusible material 24 will soften, thereby releasing the stem I 6 and permitting the spring 2| to move the stem IB to the right as shown in Fig. 4, thereby bringing the valve head I8 on to the valve seat II, and

the tapered sleeve 25 into engagement with the wall of the tapered aperture in plug 23, thus sealing off the valve stem assembly and preventing escape of fluid therethrough. The spring 2I 40 is of such length and of such design that it remains under compression after the head I8 has engaged the seat I I, thus insuring denite and positive closing of the valve.

After automatic operation of the valve, the plug 23 is removed and refilled with fusible material and thenreinserted into the'end'of the shaft I2. Preferably, before the plug is reinserted, the hand wheel I5 is rotated to bring the shaft into normal valve closing position, thus bringing the nut 20 into its recess and moving the-end of the stem I I into such position that it does not interfere with thewinsertion of the plug 23. Y Itis to be noted that in a valve as illustrated If, while 30 itl 2. -il i in the drawing, when the valve has been fully opened manually, the spring 2l Vassociated with the shaft I2 is under such compression that if or when the fusible material 24 softens and permits the valve stem I6 to move to the right, the spring is capable of exerting sufficient force fora suflicient d istance to move the stem I6 until the valve head I8 is tightly held against the valve seat II.

Furthermore, it is to be particularly noted that during any manual operation of a valve having the features of my invention incorporated therein, the spring which actuates same in an emergency, is always under constant compression, thus preserving the life of the spring during such manual oper-ation. Thus, there is rprovided a positive means for actuating the valve .in an emergency, which means remains undisturbed during the ordinary usage of the valve.

The relationship between the conical walls of sleeve and the tapered aperture in the plug 23 prevents any possibility of the spring forcing the stem out through the aperture and, in a valve having the valve head II reversely disposed, for

automatic opening of the valve, the relationshipY above described limits the movement of the stem.

A feature of my invention that is of substantial importance, particularly when the valve is being employed in connection with inflammable fluids, is the prevention of leak-age about or around the valve stem when an emergency actuation occurs. Thus, in the valve illustrated in the drawing, the tapered sleeve 25 seats against the conical inner walls of the plug 23, the fusible material 24 having become molten and forced outwardly, such seating forming a fluid-tight seal so that passage of fluid between the stem I6 and shaft I2 is prevented. Y

It is of course apparentthat various changes may be made in the embodiment of my invention above described. The scope of my invention is defined in the appended claims.

The valve proper as described herein and shown in the drawing, that is, the arrangement of parts I8, II and I, disclosed in the drawing and hereinabove referred to, are employe-d by me for purposes of illustration and without intend-l ing that such parts, or association of parts, per se, are to be considered as my invention.

What I claim is:

1. In combination, a valve casing having a valve seat, a valve head movable into and out of engagementI with said seat, a valve stem oonnected to said valve head, a tubular operating shaft cooperating with andamanually movable with respect to said casing, said stem extending into said shaft, a spring under compression interposed between said operating shaft and a portion of the stem contained within said shaft, an abutment upon the stem, a fusible member arranged adjacent the end of the shaft opposite that into which said stem extends, said spring pressing against said abutment, thereby to urge said stem toward said fusible member.

2. In combination, a valve casing having a valve seat, a valve head assembly normally adapted for movement as a unit with respect to said casing, which comprises a valve head cooperating with said valve seat, a tubular member cooper-ating with said 'casing and manually movable with respect thereto, a valve stem extending from said valve head into one end of said tubular member, a spring normally under substantially its maximum compressiom interposed between the tubular member and a portion of thev stem oontainedtherewithin, ,an` abutment adjacent its outer end, a plug having a threaded portion of non-fusible material adapted for threaded engagement with said threaded part of said shaft and having a fusible portion, a stem extending from said valve head into said operating shaft and being slidable therein, a spring forcing said stem into engagement with said fusible portion, and means carried by said stem adapted to coact with 'said non-fusible portion of said plug to limit the movement of said stem in response to actuation by said spring upon fusion of said fusible portion.

4. In a valve, a casing having a v-alve seat, a valve head movable into and out of engagement with said seat, an operating shaft having threaded connection with said casing, said operating shaft being tubular and having an axial recess at one end, a plug closing said recess and havingv a` fusible portion, a stem extending from said valve head into said operating shaft into contact with said fusible portion, a spring in said recess, and a nut on said stem engaged by said spring whereby the end of the stem is held in contact with said fusible portion, said recess havingv a portion shaped to receive said nut and to hold the same against rotation.

5. In a v-alve, a casing having a valve seat, a valve head movable into and out of engagement with said seat, an operating shaft having'threaded connection with said casing, said operating shaft being tubular and having an axial recess at one end, a plug closing said recess, said plug having an internal tapering bore and fusible material disposed therein, a stem extending from said valve head into said operating shaft and` 6. In a valve, a casing having a valve seat, aV

valve head movable into and out of engagement with said seat, an operating shaft having threaded connection with said casing, said operating shaft being tubular and closed at 'its outer end with a fusible plug, a stem extending from said valve head into sai-d operating shaft to engage said plug, and a spring holding said stem in engagement with said plug, said spring being effective to move the valve stem upon fusing of said plug and cooperating sealing p-arts carried by said stem and shaft which are adapted to be brought into sealing relationship as a result of movement of said stem upon fusion of said plug.

'7. In combination, a valve casing, a valve movable to control flow through said casing, operating means for said valve comprising a manually rotatable reciprocating member, a stem connecting said valve and said member, a fusible plug in saidy member engaging the end of said stem and a spring interposed between said member and said stem for moving said stem to locate the valve in predetermined position upon fusing of the plug and cooperating sealing parts carried by said stem and said member adapted to limit movement of said stem in response to said spring and to be brought into sealing relationship as a result of such movement.

8. In combination, a valve casing, a valve member movable to control iiow through said casing, means -associated with said valve member for manually operating same and comprising a valve stem and a fusible member associated with said stem, mea-ns for positively actuating said valve stem upon fusion of said fusiblemember, said valve operating member also comprising means which permits limited free movement of the valve stem and which effects a seal against fluid leakage along said valve stem, said means adapted to eiect said seal only upon positive emergency actuation of said valve member.

9. In combination, a valve casing, a valve member, means for manually operating said valve member to control flow through said casing comprising a valve stem, means for automatically actuating said valvestem in an emergency, the means last mentioned comprising an element which during the manual operation of the valve remains substantially undisturbed, said operating means comprising means which permits limited free movement of the valve stem and which eiects a seal along the valve stem upon completion of the movement of said stem when same has been automatically actuated.

LESTER M. GOLDSMITH. 

